The present invention relates to an apparatus for precisely cutting lengths of strip material from a continuous supply of the strip material. More particularly, the present invention relates to an apparatus which precisely locates a section of strip material adjacent a movable cutter, permitting the cutter to sever the strip material into precisely dimensioned lengths.
In certain manufacturing processes, a supply of strips of material, particularly metal, are required. The strips must be cut to exact lengths to provide certain characteristics, e.g., for generating an electrical signal at a specific frequency.
The material is usually supplied in rolls of a predetermined width and thickness. Strips of exact length are then to be cut from the roll of material such that the exact length strips can be used in manufacture of a particular item.
Due to the high degree of precision and very small tolerances allowed in the forming of the strips, the strip length may need to be varied, depending upon material variations within the roll of the strip material. Specifically, the length of the strip being cut fine tunes the final product, where the length may need to be varied to compensate for the variations in the material to be cut.
The strips are often used in a mass produced product having a low unit cost. Thus, the strips must be effectively and quickly produced in an economical and automatic manner. Additionally, the cut strips must be in a position which allows them to be inserted in or combined with other parts to produce a final product.
Conventional apparatus for cutting strips of this type are relatively slow and inefficient. Each cutting apparatus must be individually controlled by an operator, and thus, is not fully automatic. The lack of automatic operation increases the cost of production and limits the speed of production. A precisely, elongated strip is needed to form a resonator strip for a security tag. The resonator strip converts magnetic energy to mechanical energy, and then reconverts that mechanical energy back to electromagnetic energy that generates a signal. Specifically, resonator strips are magnetostrictive elements which store energy by contracting in a magnetic field. When the magnetic field is removed, the magnetostrictive elements expand and vibrate at a resonant frequency to generate an electromagnetic wave that can be received to activate a signal. The length of the resonator strip determines its frequency. Unacceptable variations in the resonator strip length will cause the generation of the wrong frequency, resulting in the security tag becoming inoperative.
An object of the present invention is to provide an apparatus for precisely cutting lengths of strip material at great speed accurately and automatically.
Another object of the present invention is to provide an apparatus for precisely cutting lengths of strip material which can compensate for variations in the strip material supplied to the cutter.
The foregoing objects are basically obtained by an apparatus for precisely cutting lengths of strip material. The apparatus comprises a supply of strip material, feed means for conveying the strip material from the supply, and a reciprocating cutter mounted downstream of the feed means. An adjustable stop is movably mounted adjacent the cutter for engaging an end of the strip material and setting a precise length of the strip material being cut. Adjustment means is coupled to the stop for moving the stop relative to the cutter along a longitudinal axis of the length of the strip material being cut.
By forming the apparatus in this manner, the apparatus can be used with a test mechanism to verify the correct length of the strip material. If the material is cut to the wrong length, for example, due to material variations in the strip material being supplied, the final product can be fine tuned by operating the adjustment means, in response to the signal from the test mechanism to move the stop, as necessary, to correct the strip material length.